Wetting agent (Photoflo) does what it says. Soap and detergents do the same thing but are not at all suitable.
NEVER EVER use soap, washing up liquid or anything similar as a substitute - all it does is put a sticky residue on the film.
I won't go into the chemistry but you need a non-ionic wetting agent that works at low concentrations. The most useful chemicals come from the polyethylene glycol group.
Ethylene glycol works fine. You know it better as car anti-freeze.
This will work fine in the short term but get the proper stuff.

I've never had any problems using unscented, mild dishwashing detergent (not soap) instead of Photo Flo as a final rinse. I use 2 drops per gallon of water. I admit I know nothing about the chemistry, but there are plenty of folks using it over at APUG, and that's good enough for me.

I've never had any problems using unscented, mild dishwashing detergent (not soap) instead of Photo Flo as a final rinse. I use 2 drops per gallon of water. I admit I know nothing about the chemistry, but there are plenty of folks using it over at APUG, and that's good enough for me.

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Fascinating. What brand, if you don't mind my asking? Something like Ivory dishwashing detergent? I keep a lot of that stuff around because you're not supposed to use "soap" on Reidel stemware, either, but Ivory is the exception because of the clean way it rinses off.

Fascinating. What brand, if you don't mind my asking? Something like Ivory dishwashing detergent? I keep a lot of that stuff around because you're not supposed to use "soap" on Reidel stemware, either, but Ivory is the exception because of the clean way it rinses off.

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Clear Ivory detergent is what I've used. Most of the time I do use Photo Flo; a couple of big bottles last me all year and it is pretty cheap. Since one local darkroom supplier went out of business, and the other isn't carrying much selection anymore, I've gone to mail ordering my supplies, and I keep my darkroom fully stocked so I don't run out of anything.

Go over to APUG and search for "detergent" and you will come up with a bunch of threads of folks discussing all sorts of crazy stuff they are using.

If you want to see some of the crazy stuff people use Photo Flo for do a google search for "photo flo detergent". You'll come up with all sorts of articles completely unrelated to photography that recommend using Kodak Photo Flo as a cleaner. The weirdest I saw was a recommendation to use it for cleaning tombstones.

Photo Flo: keeps water spots off your film, and great granny's headstone!

I've never had any problems using unscented, mild dishwashing detergent (not soap) instead of Photo Flo as a final rinse. I use 2 drops per gallon of water. I admit I know nothing about the chemistry, but there are plenty of folks using it over at APUG, and that's good enough for me.

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You wouldn't have any problems at that concentration.
If you do the maths you are diluting the detergent almost 1:95,000. At that concentration it is physically impossible for the detergent to work as a wetting agent - there aren't enough molecules to go around. So if your detergent is working it must be doing it homeopathically.
The up side is that there is not enough detergent in there to produce a film on the negs. If you are not getting drying marks then it is probable that you live in a soft water area.
You really should check out the chemistry.

And I need to improve my maths - the dilution should read ' over 1:47,000'. I forgot you use 2 drops. But it doesn't make a difference.

how many times can you use photo flo? Say you do what it says where you mix 1/3 capfull per 37 oz of water? ive used the same batch for 3 rolls now and am wondering if i should throw it out or keep using it. It seemed to work fine on all three rolls though so far.